Hope and help for triple-negative (TNBC) and other forms of hormone-negative breast cancer.

Saturday, May 24, 2014

Study Finds Clues to How TNBC Spreads

Researchers
have identified chemical signals that triple-negative breast cancer cells use
to recruit two types of normal cells needed for the cancer’s spread. The study,
which was done on mice, appears in the online early May edition of the Proceedings
of the National Academy of Sciences.

The
research focused on a chemical signal called hypoxia-inducible factor 1
(HIF-1), which cells release to help them cope with low-oxygen conditions.
Earlier, the group determined that HIF-1 helps breast tumor cells survive the
low-oxygen conditions in which they often live, and spread to other parts of
the body such as the lungs. "In breast cancer, it's not the original tumor
that kills patients, but the metastases," says Gregg Semenza, M.D., Ph.D.,
a professor and director of the Vascular Biology Program in the Johns Hopkins
University School of Medicine's Institute for Cell Engineering.

"This study adds to the
evidence that a HIF-1 inhibitor drug could be an effective addition to
chemotherapy regimens, especially for triple-negative breast cancers," Semenza
says. Several potential drugs of this kind are now in the early stages of
development, he notes.

"Blocking
one of these cell-recruiting signals in a mouse's tumor made it much less
likely to metastasize or spread," Semenza says. "If a drug can be
found that safely blocks the same signal in humans, it could be a very useful
addition to current treatment—particularly for patients with
chemotherapy-resistant tumors."

Also
in a previous study, Semenza's group found that HIF-1 induced adult mesenchymal stem cells to
release a signal to nearby breast cancer cells, which made them more likely to
spread. The researchers suspected this communication might run both ways and
that the stem cells' presence might also help the cancer to recruit the host
animal's white blood cells. Breast cancers need the support of several types of
host cells in order to metastasize, including mesenchymal stem cells and one
type of white blood cell, Semenza notes.

Studying
tumor cells grown in a
dish, Semenza's team used chemicals that blocked the functions of various
proteins to map a web of signals between breast cancer cells, menenchymal stem
cells and white blood cells. One positive feedback loop brought mesenchymal stem cells close in to the breast cancer
cells. A separate loop of signals between the stem cells and cancer
cells caused the cancer cells to release a chemical "beacon" that
drew in white blood
cells.

The
concentrations of all the signals in the web were increased by the presence of
HIF-1—and ultimately, by low-oxygen conditions.

The
team then used genetic engineering to reduce the levels of the cell-recruiting
signals in breast cancer cells and implanted those cells into female mice.
Compared with unaltered breast cancer cells, those with reduced recruiting
power grew into similar-sized tumors, Semenza says, but were much less likely
to spread.

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Surviving Triple-Negative Breast Cancer: Hope, Treatment, Recovery

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Patricia Prijatel

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Welcome

When I was diagnosed with hormone-receptor-negative breast cancer, I required a positive attitude of myself—I was not going to let a disease have the upper hand. I hope I can share some at that attitude with you while I offer what I have learned in my trek through this disease as a patient and medical writer.

It's a given that life ends in death. Cancer just makes you face that inevitability more directly than you might have before. To me, that means living fully right now.

Three Mountain Dogs, a children's book by Patricia Prijatel

Triple-negative breast cancer (TNBC) lacks hormone receptors for estrogen, progesterone, and Her2/neu. It affects about 20 percent of all those with breast cancer. This blog offers information and hope for those with TNBC and other forms of hormone-negative breast cancer.

Calm Spirit Note Cards

Blank greeting cards with the Calm Spirit image are available in packets of 6. They're ideal for sending a personal message of encouragement to anyone living with cancer. Boxes of six are available for $10.00 and can be ordered by contacting my friend Madlyn at madlyn.ferraro@ gmail com. Individual cards are $2.50 each.